Improvement in paper pulp or stock



HENRY LOWE, OF BALTIMORE, MARYLAND.

iMPRGVEENT lN Parse new on cross Bpecificatiou forming part of Letters Patent No. diflllhfi, dated August 20, 1861.

To all whom it may concern:

Be it known that I, HENRY LOWE, of Bnlti I more, in the county of Baltimore and State of Maryland, have invented a new and useful Improvement in the Manufacture of Paper; and I do hereby declare that the following is a full and exact description thereof.

After many years experiment'iu the manufactureof paper I have discovered that it is an improvement to reduce the fibrous matter of many difierentpaper-ma-kin g materials hav ing a very short fiber much further or to a much greater subdivision than it has been customary by the old methods.

Heretofore paper-makers have been careful not to reduce the stock too far, supposing that p a certain considerable length of fiber must be preserved in order to make paper. When papenstoek has by chance been reduced beyond such old standard length of fiber all manufacturers have regarded 'the same as spoiled or killed by the too great reduction or suhdi vision of the'fiber;but I find that this killed stock maybe revived by further reduction of the fibers, so as to make paper, and often bet-Q ter paper than that made from the same original stock according to the old practice of long fiber. Thus I have established a new theory of paper-making from short fiber and applied the same practically to different materials in the manufacture of different kinds of paper.

My invention is intended for paper-stock having a very short natural fiber; and it consists in reducing'snch materials as nearly as possible to the separation of the ultimate fibers (as deposited by nature) in order to make a stronger and better paper, and to enable manufacturers to use killed stock or materials, which,

according to the old-theory, have a-fiherI too short for paper-making.

In the practical application of my invention to did'erent papenstocks the details of treatment maybe somewhat varied in order most readily toaceomplish the same common result according to one common principle, and the details of treatment are varied only for the sake of economy and convenience. By this plan many fibrous substances hitherto regarded as worthless on account of their tendency to produce short fiber only may be worked with success,

giving good and often very excellent paper.- The following, general description will illustrate my invention, yet the manufacturer must vary the same according to circumstances and agreeably to my new mode of working short fiber: Take, for instance, reeds, straw, or Manila hemp and first treat the same according to the known methods for the reduction of such substances preparatory topulping. Then, instead of completing the process of reduction by the pulping process, as is common. (but which will not succeed at all width reeds,) take this partially-reduced stock and subject the same toforther chemical and mechanical treatment until the stock is spoiled or killed according to the old theory, because the ii are .havebecome too short. After the short fibers have been subdivided as nearly as possible to their ultimate natural length and. the foreign matter broken up and washed out; the stand is pulped and then feltedin the usual manner.

1 In order to separate the fibers of reade straw, and Manila. hemp, I recommendbciling the same in a solution of caustic soda in a rotary boiler under a'highpressure-say 135Fahrenhells-the boiler being moved about iive revolotions per minute. This treatment may be continued twelve hours or more, according to the efieots or results. The agitation of the stock greatly facilitates the separation of the fiber and the breaking up of the insoluble foreign matter. which in the common method of long fiber prevents the fibers from coming tc- -ter, at 1?; to $9 Banme, the same as used in bleaching straw fiber. When the bleach-is nearly exhausted the stufiTmay be put into the old grinding-engine-(not to be drawn. out or listed; to be pounded, in order to makethe stuii' hold the water and to bring it-into condition to proper! felt. This last treatment may be oriented by ing'slauds or Jordans or other engine; but it'is veryimportant that-the knives are dull, so as to give considerable surface, and thus pound instead of cutting he fiber.

For tissuepaper the fibers must be reduced to extreme subdivision and great care taken in the washing in orderto obtain a, strong paper.

I confine my claim to the peculiar improvement. above set forth, in accordance with my new theory-the shorter the fiber the better the paper-as distinguished from the common theory-and practice, which required a standard length of fiber in order to felt.

Having thus fully described my invention, what I claim, and desire to secure by Letters Patent of the United States, is-- The above-described paper stock or pulp having a short fiber, as a new article'of manufaeture, the same being made from killed or spoiled stock or from vegetable substances having naturally a very short fiber, substantially as set forth.

HENRY LOWE,

Witnesses:

Elm. F. BROWN, DANIEL BREED. 

